Portable Turbidity Meter
430-260
OPERATING INSTRUCTIONS
Portable Turbidity Meter
430-260
ELE International
Chartmoor Road, Chartwell
Business Park, Leighton Buzzard
Bedfordshire, LU7 4WG England
Sales: Civil +44 (0) 870 777 7706
Sales: Env. +44 (0) 870 777 7717
Service: +44 (0) 870 777 7727
fax: +44 (0) 1525 249249
email: ele@eleint.co.uk
http://www.ele.com
Distributor:
ELE International
Soiltest Product Division
PO Box 389
Loveland, CO 80539
USA
phone: +1 (800) 323 1242
fax: +1 (970) 663 9781
email: soiltest@eleusa.com
http://www.eleusa.com
ELE International, a division of Danaher Corporation
ELE International, a division of Danaher UK Industries Ltd
In the interests of improving and updating its equipment, ELE reserves the right to alter
specifications to equipment at any time ELE International 2005 ©
1
Issue 1
Portable Turbidity Meter
430-260
Contents
Section
Page
1
Preliminary Examination
3
2
General Description
3
3
Principle of Operation
4
4
Functional Description
6
5
Specifications
7
6
Operational Guide
7
Measurement Procedure
8
7
How To Ensure Accurate Measurements
11
Sources of Interference
12
Calibration
12
Calibration Procedure
12
How To Ensure Accurate Calibration
16
Standard Suspension
16
Viewing the Calibration Date
17
8
Battery Replacement
18
9
LCD and Error Codes
20
2
Issue 1
Portable Turbidity Meter
430-260
Please read these operating instructions carefully before using the
instrument. They will provide you with all the necessary information for the
correct use of the instrument, as well as a more precise idea of its versatility
in a wide range of applications.
This instrument is in compliance with the C E directives.
1
Preliminary Examination
Remove the instrument from the packing material and examine it to make
sure that no damage has occurred during shipping. If there is any damage,
notify ELE International.
The 430-260 is supplied complete with:
•
•
•
•
•
•
•
1.5V AA size Batteries (4 each)
Glass Cuvette
Cap
Cal. solutions
Cleaning solution
Cleaning tissue
Rugged carrying case
Note: Save all packing material until you are sure that the meter functions
correctly. All defective items must be returned in its original packaging with
the supplied accessories.
2
General Description
With the 430-260 turbidity meter, turbidity measurements can be performed
with high precision in the field as well as in the laboratory. The 430-260
turbidity meter is a hand-held, microprocessor-based, battery operated
instrument used to determine the turbidity of water and wastewater. The
meter covers a 0-1000 FTU range in two scales: 0.00 to 50.00 FTU and 50
to 1000 FTU. The auto-ranging feature of the instrument sets the appropriate
range for the measurement.
Note: The 420-360 has been designed according to the ISO 7027
International Standard, consequently the turbidity measurement unit is
the FTU (Formazine Turbidity Unit). FTU is identical to the other
internationally recognised unit: NTU (Nephelometric Turbidity Unit).
The 430-260 is a portable turbitity meter with the C E mark, in compliance
with the European directives, ensuring low emission values and accurate
measurements in the presence of electromagnetic fields.
The meter is housed in a rugged and lightweight case with an easy-to-read
LCD. To save battery life the instrument is equipped with an automatic shutoff feature which is activated after 4 minutes of non-use.
3
Issue 1
Portable Turbidity Meter
430-260
The meter is very simple to use. All operations can be carried out with only
four keys and troubleshooting functions can be performed with displayed
error code guides. An exclusive positive-locking system guarantees that the
cuvette is firmly placed in the cell. The keypad is water-resistant and can be
wiped with a moist cloth for quick clean-ups.
The one-point calibration at 10 FTU* can be easily performed using the
available standard. In addition, the 430-260 is the first portable turbidity
meter that allows it to store the last calibration date and to retrieve it at the
user’s convenience.
ELE International has chosen 10 FTU* as the calibration point because
it is the value that best fits the water turbidity measurements in
different applications, from drinking water to wastewater treatment.
ELE International uses the primary standard AMCO-AEPA-1 to avoid all
formazine-related problems. Formazine is a very toxic, unstable substance,
which requires particular care: its standards have to be prepared only a few
minutes before performing the calibration, and cannot be re-used because of
their short life. ELE International standards are extremely stable, can be reused, and last up to six months, if free from contamination. The 430-260 can
be used with both standards.
3
Principle of Operation
The 430-260 has been designed to perform measurements according to
the ISO 7027 International Standard.
The instrument functions by passing a beam of infrared light through a
vial containing the sample being measured.
The light source is a High Emission Infrared LED with a wavelength
peaking at 890 nm, ensuring that the interference caused by colored
samples is minimum.
A sensor, positioned at 90º with respect to the direction of light, detects
the amount of light scattered by the undissolved particles present in the
sample. The microprocessor converts such readings into FTU* values.
* 1 FTU = 1 NTU
4
Issue 1
Portable Turbidity Meter
430-260
As noted above, FTU unit is equal to the NTU unit. However, there are
other known measurement units for turbidity: Jackson Turbidity Unit
(JTU) based on the old method of Jackson’s candle, and Silica Unit
(mg/L of SiO2). For your reference the conversion table between these
measurement units is shown below:
JTU
FTU/NTU
SiO2 (mg/L)
JTU
1
19
2.5
FTU/NTU
0.053
1
0.13
SiO2 (mg/L)
0.4
7.5
1
* 1 FTU = 1 NTU
5
Issue 1
Portable Turbidity Meter
430-260
4
Functional Description
Measurement Cell
DATE/⇒ Key
LCD
READ/⇑ Key
ON/OFF Key
CAL Key
1)
2)
3)
4)
5)
6)
Measurement Cell
LCD (Liquid Crystal Display)
ON/OFF Key
CAL Key, to enter the Calibration Mode
READ/⇑ Key, to perform measurements and to set the date (day
and month) of the last calibration
DATE/⇒ Key, to display the last calibration date and to select
either the month or the day of last calibration
6
Issue 1
Portable Turbidity Meter
430-260
5
Specifications
430-260
Range
0.00 to 50.00 FTU *
50 to 1000 FTU *
0.01 and 1 FTU *
Resolution
Accuracy
±0.5 FTU* or ±5%
of reading (whichever greater)
EMC Typical Deviation
±2% Full Scale
Light Source
High Emission Infrared LED
Light Source Life
Life of the instrument
Light Detector
Silicon Photocell
Power Source
4 x 1.5V AA batteries
Battery Life
60 hours or 900 measurements
Auto Shut-Off
After 5 minutes
Operating Conditions
0 to 50ºC (32 to 122ºF);
0 to 95% RH (non-condensing)
Dimensions
220 x 82 x 66 mm
(8.7 x 3.2 x 2.6”)
Weight
510 g (18 oz.)
* 1 FTU = 1 NTU
6
Operational Guide
To prepare the instrument for taking measurements, first install the
batteries (see Battery Replacement section on page 18) and then turn
the instrument on.
To maximize the battery life the meter is automatically switched off after
5 minutes of non-use. To reactivate it, simply press the ON/OFF key.
7
Issue 1
Portable Turbidity Meter
430-260
Measurement Procedure:
•
Turn the meter on by pressing the ON/OFF KEY.
•
The meter will carry out a self-test displaying a full set of figures.
After the test, the LCD will change to the measurement mode.
•
When the LCD displays “----“ the meter is ready to measure.
•
Fill a clean cuvette up to one quarter inch (0.5 cm) from its rim with
the thoroughly agitated sample.
•
Allow sufficient time for bubbles to escape before securing the cap.
Note: do not over-tighten the cap.
8
Issue 1
Portable Turbidity Meter
430-260
•
Wipe the cuvette thoroughly with the lint-free tissue supplied before
inserting into the measurement cell. The cuvette must be completely
free of fingerprints and other oil or dirt, particularly in the area where
the light goes through (approximately the bottom 2 cm/1 inch of the
cuvette).
•
Place the cuvette into the cell and check that the notch on the cap is
positioned securely into the groove.
•
The mark on the cuvette cap should point towards the LCD.
9
Issue 1
Portable Turbidity Meter
430-260
•
Press the READ/⇑ key and the LCD will display a blinking “SIP”
(Sampling in Process). The turbidity value will appear after
approximately 25 seconds.
•
Even though the 430-260 covers a very wide range of turbidity
values, for very accurate measurements of samples exceeding 40
FTU*, Standard Methods require dilution. In such cases, the correct
amount of Cal. solution or turbidity-free water to be added to the
sample can be calculated as follows:
Vos = 3000 / T
where: Vos =
T
E.g.:
=
volume of sample (mL) to be combined with Cal.
solution to obtain the final volume of 100 mL.
430-260 reading (exceeding 40 FTU*)
430-260 reading = 200 FTU *
3000 / 200 = 15 mL (Vos)
15 mL (Vos)+85 mL (Cal. solution) = 100 mL
At this point take a sample of this solution and measure turbidity.
The correct turbidity value of the original sample will be:
Tn x 100 mL / Vos = Ta
where: Tn = new 430-260 reading
Ta = actual turbidity value of the original sample
*1 FTU = 1 NTU
10
Issue 1
Portable Turbidity Meter
430-260
How to Ensure Accurate Measurements
•
Each time the cuvette is used, tighten the cap to the same degree.
•
Discard the sample soon after the reading is taken to avoid
permanently clouding the glass.
•
All glassware used to contain the standards and the samples should
be maintained clean, washed with cleaning solution and rinsed with
Cal. solution or turbidity–free water.
•
Collect the samples in clean glass or plastic bottles, fit stoppers and
perform the analysis quickly. If unavoidable, store the sample in a
cool, dark place, but not for longer than 24 hours (the sample needs
to be kept at room temperature prior to the analysis).
•
To obtain a representative sample, gently, but thoroughly, mix it
before samples are taken. Do not shake it (to prevent air bubbles)
and do not let the sample settle.
•
It is recommended to monthly calibrate the meter with the supplied
Cal. solution @ 10 FTU* standard or more frequently for greatest
accuracy.
•
Before inserting vials into the instrument, wipe them with the soft,
lint-free tissue supplied. Handle vials so that no fingerprints can get
on the areas where light passes (approximately 2 cm/1 inch from the
bottom of the vial).
If you experience any problems in taking measurements, please contact
ELE International.
1 FTU = 1 NTU
11
Issue 1
Portable Turbidity Meter
430-260
Sources of Interference
•
Presence of floating debris and coarse sediments which settle out
rapidly will give false readings.
•
The infrared light source used for the 430-260 turbidity meter,
according to ISO 7027 International Standard, can efectively
minimize errors due to colored dissolved substances. This effect,
named “true color”, is a common interference for most commercially
available instruments operating in the range of visible light.
•
Air bubbles and the effect of vibrations that disturb the surface of the
sample will give false results.
•
Dirty glassware could also affect readings along with scratched or
edged vials.
7
Calibration
A monthly calibration is recommended. To check the date of the last
calibration, simply hold the DATE/⇒ key down for a few seconds.
A more frequent check of the instrument is suggested by using the supplied
standard solution.
Calibration Procedure
•
Turn the meter on and wait for the display to show “----“.
•
Press the CAL key once, the “CAL” message will blink on the display for
about 6 seconds, then the calibration mode stops.
12
Issue 1
Portable Turbidity Meter
430-260
•
While the “CAL” message is still blinking, press CAL again. The
instrument is now in the calibration mode and a “CL” will appear on the
lower part of the display. The date of calibration can be edited now by
simply pressing the DATE/⇒ key. To scroll to the correct number press
the READ/⇑ key. The default blinking parameter is the month, on the left
hand of the display (MM.DD).
•
To confirm the displayed data values and to go to the next step,
press the CAL key once. A blinking “ZERO” message will appear.
•
Take the Cal. solution bottle containing the ZERO FTU* Standard (or
turbidity-free dilution water) and fill the measurement cuvette.
13
Issue 1
Portable Turbidity Meter
430-260
Note: in order to minimize any error introduced by the cuvette, it is
recommended to use, during calibration, the same cuvette you are
going to use to perform the measurement.
•
Insert the cuvette with the Cal. solution @ ZERO FTU* standard
solution (or turbidity-free dilution water) into the measurement cell
and press the CAL key. A blinking “SIP” message indicates that the
instrument is performing the measurement. After approximately 50
seconds the instrument will ask for the Cal. solution standard
solution @ 10 FTU* by displaying “10.0”.
•
14
Issue 1
Portable Turbidity Meter
430-260
•
Repeat the same procedure with Cal. solution @ 10 FTU* standard
solution.
•
Insert the cuvette with the Cal. Solution AMCO-AEPA-1 standard @
10 FTU* into the measurement cell and press the CAL key again.
•
After approximately 50 seconds the LCD will display “----“.
Now the instrument is calibrated and ready for use.
Adding the third calibration point (500 FTU)
•
After the second calibration point (10.00 FTU) has been accepted,
the meter will display “500”, asking for the 500 FTU solution to be
placed in the cuvette holder.
Note: At this point the user can exit the calibration mode and save
the two-point calibration by pressing READ.
15
Issue 1
Portable Turbidity Meter
430-260
To perform a three point calibration, place the 500 FTU standard solution
in the cuvette holder.
•
Press CAL : “SIP” and “CL” will start blinking.
•
After approximately 30 seconds, the display will show “----“.
Now the meter is calibrated and ready for use.
Note: If “ERR1” is displayed, the calibration data are maintained.
How to Ensure Accurate Calibration
The instructions listed below should be carefully followed during testing
and during calibration:
•
All glassware that comes into contact with standards should be
maintained clean. Wash with cleaning solution and rinse with Cal.
solution or turbidity-free water.
•
Rinse the vial twice with 5 ml of the liquid to be tested. This removes
the effect of any previous liquid and any dust or foreign matter that
may be present inside. Gently pour the liquid down the side of the
vial to reduce air bubbles (no mixing is required when Cal. solution
and AMCO-AEPA-1 standards are used).
•
Before inserting the vial into the instrument, wipe it with the soft, lintfree tissue supplied. Handle vials so that no fingerprints can get on
the areas where light passes (approximately 2 cm/1 inch from the
bottom of the vial).
16
Issue 1
Portable Turbidity Meter
430-260
Standard Suspension
Presently there are only two recognised primary standards: AMCOAEPA-1 and formazine.
ELE International supplies the 430-260 with the AMCO-AEPA-1 which
has a much longer shelf life at all concentrations (approximately six
months, if free from contamination). In addition no special handling or
disposal is required and a much higher stability of suspended particles
has been observed.
On the other hand, formazine is a very toxic substance, generated by a
known carcinogen, its stability is poor (particles flocculate and settle
quickly). Lower concentrations change value within a few days or hours
after dilution from stock solutions.
The consistency of the 430-260 readings by using both standards has
been separately established by Advanced Polymer Systems and ELE
International.
Additional documentation about the formazine standard and more
complex calibration procedures are available upon request.
Viewing the Calibration Date
•
Turn the meter on and wait for the display to show “----“.
17
Issue 1
Portable Turbidity Meter
430-260
•
Press and hold the DATE/⇒ key and a “MM.DD” message appears
while the key is held.
Note: The displayed date is the date that was input by the user at the
beginning of the last calibration.
8
Battery Replacement
All components have been selected to minimize current drain without
compromising functionality.
In order to minimize the battery consumption, the meter is equipped with
an auto shut-off function which switches the meter off after 5 minutes of
non-use.
The power source is 4 x 1.5V batteries with an expected life of 60 hours,
or over 900 measurements.
To always grant accurate measurements, the batteries are monitored to
ensure that readings are not taken when there is insufficient power.
A “LO BAT” indication will appear on the lower right hand side of the
display when the batteries are weak and require replacement; at this
point the instrument is able to perform only 50 more measurements.
18
Issue 1
Portable Turbidity Meter
430-260
A “-BA-“ indication will appear on the display when the batteries are too
weak to perform measurements; the message appears for a few
seconds, and then the meter will automatically switch off; at this point it
is absolutely necessary to replace the batteries to use the instrument.
Battery replacement must only take place in a non-hazardous area using
the battery types specified in these operating instructions.
To install or replace the batteries, turn the unit off and unscrew the 2
screws located on the back of the battery cover.
Remove the battery cover exposing the battery compartment.
19
Issue 1
Portable Turbidity Meter
430-260
Place the batteries in the compartment while paying attention to the
polarity.
After the batteries have been installed, replace the battery cover on the
back of the instrument and tighten the 2 screws.
9
LCD and Error Codes
The 430-260 will display several different LCD codes in different situations to
help the user to operate the meter.
This indicates that the meter is in a ready state and measurement or
calibration can be performed.
20
Issue 1
Portable Turbidity Meter
430-260
This indicates that the Calibration Mode is active. If the CAL key is not
pressed within 6 seconds, the meter will automatically switch to the
Measurement Mode.
This indicates that the Calibration Date Setting Mode is active.
This indicates a 0 FTU* standard calibration is required.
This indicates that calibration is performed.
This indicates a 10 FTU* standard calibration is required.
21
Issue 1
Portable Turbidity Meter
430-260
This indicates the last calibration date (MM.DD).
This indicates that measurement is performed.
This indicates that batteries are weak and have to be replaced. When this
message appears, the instrument is able to perform 50 more measurements.
This indicates that batteries are too weak to perform measurements. The
message appears for a few seconds, then the meter will automatically switch
off. At this point it is absolutely necessary to replace the batteries.
* 1 FTU = 1 NTU
22
Issue 1